I have been able to repeatedly reproduce a Publisher user interface hang issue when running Windows 10 under any display scaling larger than 100%.
If I set Windows display scaling to 130%, sign out, sign in, start Publisher, then use File / New to create a new document, the document gets created, but the UI stops responding and Task Manager shows Publisher's CPU usage spinning between 15% and 17%. The only way out is to use Task Manager to kill Publisher and go back to 100% display scaling. I use three 4K monitors running under nVidia drivers (up to date), Windows 10 Pro 10.0.18363 Build 18363 with 32 GB of RAM.
I usually run at 100% scaling because all other applications I use are OK with it, but in Affinity applications, the menu and dialog fonts are too small at 100% unless I move my face to within about 8" of the screen. Affinity applications really need a way to scale the user interface without having to scale the entire OS display.
AffPublisher-1.0-folder minus Samples.zip